In the manufacture of refrigerator cabinets, there is usually an outer shell of sheet metal, an inner liner of plastic and polyurethane insulation foamed in place between the inner liner and the outer shell. To achieve acceptable cabinet strength, some adhesion is necessary between the foam and the shell and liner. With such adhesion, the cabinet cannot react to forces of impact, twist, or more commonly, thermal expansion and contraction.
This reaction problem is caused by a combination of natural foam adhesion, freezer-refrigerator surface temperature differential, and "lock-up" which occurs around the normal surface variations of shelf slides, studs, air ducts, etc. When exposed to a large temperature differential between the refrigerated compartments, particularly the freezer space, and the ambient conditions outside of the shell, and when further subjected to large temperature swings, the combination of high coefficient of expansion/ contraction for plastic and the adhesion factor, creates excessive tensile stresses in the liner causing it to crack and pull apart at the location of highest stress.
The above-discussed problems are magnified in larger liners which are used in larger refrigerators, such as on the order of 25 cubic feet.
The present invention is intended to solve one or more of the problems discussed above in a novel and simple manner.